Increased Risk of Colorectal Cancer in Ulcerative Colitis Patients Diagnosed after 40 Years of Age
Bibliographic record
Abstract
BACKGROUND: The association between ulcerative colitis (UC) and colorectal cancer (CRC) is well established. Retrospective data show a 5.4% CRC incidence rate among patients with pancolitis and suggest that cancer surveillance should be provided to patients following eight to 10 years of extensive UC. AIM: To identify premalignant risk factors for UC patients and to determine whether current recommendations for cancer surveillance need reviewing. PATIENTS AND METHODS: A retrospective audit was conducted of adult patients with UC who were diagnosed with CRC between 1991 and 2002 in five hospitals in Edmonton, Alberta. RESULTS: Thirty-one cases of CRC (68% male) were identified. In this group, the mean ages at diagnosis were 44.4 years for UC patients and 60.1 years for CRC patients. For patients in whom the initial data of diagnosis of UC could be determined (n=29), the median duration of UC at the time of CRC diagnosis was 16 years. Patients diagnosed with UC after 40 years of age (n=15, mean age 64 years) progressed more rapidly to CRC than patients diagnosed before 40 years of age (n=14, mean age 23 years). The median durations of UC before development of CRC were 22 years and 10 years, respectively, for patients with a diagnosis of UC before and after 40 years of age (OR 11.5, 95% CI 2.41 to 20.16; P=0.00029). Only four patients (13%) were enrolled in an appropriate cancer-screening program. Nine of these UC patients (29%) who were older than 40 years of age developed CRC before the 10-year point. CONCLUSIONS: In the present study, patients diagnosed with UC after 40 years of age developed CRC more rapidly than those diagnosed before 40 years of age. This finding suggests that patients who are diagnosed with UC after 40 years of age should undergo CRC surveillance earlier than current recommendations.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.002 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".